unit testing - Python unittest failure when results appear equal -

i'm running series of unit tests on rpn calculator i've put together. calculator can mix integers, floats, , picas. need able calculate using picas typesetting work i'm doing.

for reason, 1 of unit tests failing:

failure traceback (most recent call last):   file "/users/andrew/developer/pyrpn/test_rpn.py", line 112, in test_pica_subtracted_from_pica     self.assertequal(self.calc.rpn(['10p3', '2p1', '-']), ['8p2']) assertionerror: lists differ: ['8p2'] != ['8p2']  first differing element 0: '8p2' 8p2    ['8p2'] 

i can't see why. simplify took list out of equation , compared directly string:

failure expected :'8p2' actual   :'8p2'  <click see difference>  traceback (most recent call last):   file "/users/andrew/developer/pyrpn/test_rpn.py", line 112, in test_pica_subtracted_from_pica     self.assertequal(self.calc.rpn(['10p3', '2p1', '-']).pop(), '8p2') assertionerror: '8p2' != '8p2' 

it still fails. cannot see why '8p2' != '8p2'. running in pycharm if click see difference, tells me there no differences, , content identical, yet test fails. fails command line well.

i've put same test in doctest:

""" >>> rpn().rpn(['10p3', '2p1', '-']) ['8p2'] """ 

and passes without problem.

---

mcve:

import re import unittest   class pica(object):     def __init__(self, points):         self.points = points      def __repr__(self):         whole_points = int(self.points / 12)         sub_points = self.points - (whole_points * 12)         return "'%rp%r'" % (whole_points, sub_points)      def __sub__(self, other):         if type(other) pica:             return pica(self.points - other.points)   class rpn:     def __init__(self):         self.oper_dict = {'-': rpn.pop_two_and_sub}         self.pica_pattern = re.compile("(\d+)p(\d+)")      def pop_two_and_sub(self, terms):         terms.append(terms.pop() - terms.pop())      def rpn(self, terms):         result = []         term in terms:             if term in self.oper_dict:                 self.oper_dict[term](self, result)             elif self.pica_pattern.match(term):                 match = self.pica_pattern.match(term)                 result.append(pica(int(match.group(1)) * 12 + int(match.group(2))))             else:                 raise syntaxerror         return result   class testpica(unittest.testcase):     def test_pica_subtracted_from_pica(self):         self.assertcountequal(rpn().rpn(['2p1', '10p3', '-']), ['8p2'])   if __name__ == '__main__':     unittest.main() 

when run python 3.5, following error:

failure traceback (most recent call last):   file "/users/andrew/developer/pyrpn/mvce.py", line 42, in test_pica_subtracted_from_pica     self.assertcountequal(rpn().rpn(['2p1', '10p3', '-']), ['8p2']) assertionerror: element counts not equal: first has 1, second has 0:  '8p2' first has 0, second has 1:  '8p2' 

ok, found difference. python 3 has more support unicode, doesn't show encoding in effect when printing unicode string, why printed same though had different types:

1. <class '__main__.pica'>
2. <class 'str'>

in order assertion work, either smarter compare needed, or else strings need put in common format before calling assert methods.